Hammer and wear-plate structure for attrition pulverizers



y 1953 w. c. ROGERS 2,639,863

HAMMER AND WEAR-PLATE STRUCTURE FOR ATTRITION PULVERIZERS Filed. July 21, 1950' Ii Sheets-Sheet 1 INVENTOR WA YNE 6. [P0 cares ATTORNEY May 26, 1953 w. c. ROGERS 2 ,639,863

HAMMER AND WEAR-PLATE STRUCTURE FOR ATTRITION PULVERIZERS Filed July 21, 1950 s Sheets-Sheet 2 w 7 32 5-4 38 if; 46 g $149433! 42 40 SEW ,50 52 44 42 8/ arl-7" 5 -45 53 4/ 49 i 57 5 57 34 Fig. INVENTOR g 4 I WAY/v5 C. ROGER:

ATTORNEY w. c. ROGERS HAMMER AND WEAR- PLATE STRUCTURE FOR ATTRITION RULVERIZERS Filed July 21, 1959 May 26, 1953 3 Sheets-Sheet 5 F, 11 INVENTOR WAYNE C. ROGE BY Wwf 43 ATTORNEY within each opening there is mounted a stationary pulverizing element or .peg' 29 which extends.

toward the rotor disk. These pegs 29 may be con-' structed as disclosed in the same Craig patent.

The present invention is principallyconcerned with the construction of the pulverizer rotor, including the disk 22 and the various parts mounted thereon. As best shown in Fig'." 3fthe disk' is provided on its outlet zone side with an outer circular row of circular recesses or counterbores 3i and with an inner circular row of circular recesses or counterbores 32. 'I'heinnerrecesses32 are equal in number and in size to the outer recesses 3|, and each inner recess is somewhat offset rearwardly from the corresponding outer recess. A relatively small hole 34 extend through the disk within each outer recess 3|, and a similar hole 35 extends throughthe disk within each inner recess 32, the centers of these holes being slightly offset rearwardly from the centers of the corresponding recesses. A circular row of somewhat larger holes 36 extend through the disk intermediate the inner and outer rows of recesses, each hole 36 being located substantially on the same radius of the disk as the corresponding inner recess 32. On its inlet zone side the disk is provided with a circular row of circular recesses 38 which are axially aligned with the corresponding outer recesses 3 l.

The rotor disk 22 provides a support for a number of revoluble impact elements or pegs 40, one of which is shown in perspective in Figs. 6 and 7. Each of these elements comprises a generally L-shaped integralstructure having one leg 4| forming a base, a second leg 42 extending at approximately right angles from the front portion of the base and having a flat front surface,

and two ribs 44 which connect the opposite edge portions of the leg 42 to the base;leg 4l. The

base leg M is of circular form to fit within a recess 3| or 32 of the rotor disk, and a hole 45 extends through :this leg in aposition offset-slightly to the rear from the center of the base so that V the hole 45 will register with a hole 34 or (as the case may be) in the disk at assembly. The fiat front surface of the leg 42 is protected from abrasion by means of varmor plate 46 applied thereto. This armor plate comprises four flat rectangular pieces of an extremely hard material, such as tungsten carbide in either the cemented form or the cast form.v The main body of the element .40 is preferably made of steelor other strong tough metal, and the armor plate i may be secured thereto by silver soldering or brazing. It will be seen that theelements 49 are arranged in two concentric circular rows, with the armored legs 42 extending into the outlet zone 25 and interfitting with the stationary pegs 29.

On the inlet zone side of the rotor diskthere is mounteda circular row of impact elements or pegs 48. Each element 48 comprises a generally L-shaped-integral structure of steel or the like having one leg 49 forming a base, a second leg 50 xt d at appr x m te ti h 1 .;i

the front portion of the base and having a flat front surface, and two ribs 52 which connect the opposite edge portions of the leg 50 to the base leg 49. The base leg 49 is of circular form to fit within a recess 38 of the rotor disk, and a hole 53 extends through this leg in a position offset slightly to the rear from the center of the base, so that the hole 53 will register with a hole 34 in the disk at assembly. The fiat front surface of theleg 50 is protected from abrasion by means of armor plate 54 (Fig. 4), preferably tungsten carbide, appliedthereto as in the case of the elements The elements 40 and 48 are of similar construction as shown, the only difference being that the legs .42 of-the elements 40 are somewhat longer than the corresponding legs of the elements 48. It will be noted that the legs 50 extend into the inlet zone 24.

. In order to hold the impact elements 43 and 48 firmly in place on the disk 22, and to protect the disk as well as the base portions of the impact elements from abrasion, there are provided two circular rows of rotor wear plates 59 and 51. The plates 56 are mounted on the outlet zone side of the disk, whereas the plates 51 are mounted on the inlet zone side of the disk. Each of these plates is shaped as a narrow circular ring sector, there being one plate 56 and one plate 51 for each of the holes 36 in the rotor disk 22.

One of the plates 56 is shown in Figs, 8 and 9.

This plate is provided with a cylindrical boss 59 of the proper size to fit closely within the corresponding hole 33 in the rotor disk. The plate also has two holes 69 and 6| therethrough which register at assembly with the holes 34 and 35 respectively in the rotor disk. On the side toward the rotor disk the holes 60 and GI are surrounded by annular ribs 63 which engage the bases 4| of the impact elements 40 at assembly. A recess 65 is provided around each hole 60 and 6| on the side away from the rotor disk. Openings 66 and 67 extend through the plate in front of the holes 50 and M respectively, these openings being approximately U-shaped and of such size that the legs 42 and ribs 44 of the impact elements 40 by annular ribs 13 and M respectively. At assembly the rib 13 will engage the base 49 of one impact element 43, while the rib 14 will engage the rotor disk. A recess 15 is provided around each hole 10 and H on the side away from the rotor disk. -An opening 11 extends through the plate; 1 in front of the hole 13, this opening being approximately U -shaped and of such size that the;

leg 59 and ribs 52 of one impact element 48 may extend therethrough at assembly.

, Referring now particularly to Figs. 1, 4 and r 5, it will be seen that with the various parts of the rotor assembled the bases 4! of the two circular rows of impact elements 46 will belocated in the recesses 31 and 32 of the disk 22, while the bases 49 of the single circular row of impact elements '48 will be located in the recesses 38. An outerrow of bolts 89 will extend through the groups of aligned holes '19, 53, 34, 45, and 60, and as these bolts are tightened the plates 56 and 51 7L5 will be clamped against tlhe bases 4| and 49 rej spectirely to force these parts against thelrotor -.disk- ::Similarlyaninner.rowrofvbolts 8i,-wil1:exten-d through the. groups. of :aligned holes H5535, 45, and SI, and as these bolts are tightened the plates 56 witl;.be'-;.clamped againstrthe bases 4| of their-marrow, of impact elements40 ;.to force thesebases ;against...the ,rotor .disk, ;while,-,,.the plates 51.will be clamped directly against themtor disk. Thus ,thesvariousareyolying parts will be held firmly together. The heads of the bolts will lie within the recesses 15, whereas the nuts at the other ends of the bolts will lie within the recesses 65.

In the operation of the invention the material to be pulverized will be carried successively through the inlet zone 24, the annular passage 26, and the outlet zone 25 by a current of air. This material will be considerably broken up by the impact elements 48 and it will then be reduced to a fine powder by the cooperative action of the impact elements 40 and the stationary pegs 29. The projecting legs of the elements 40 and 48 will be protected from wear by the tungsten carbide armor 4E and 54 on their front faces. The base legs of these elements will be protected from wear by the wear plates 56 and 51, which completely cover these base legs. Consequently the impact elements will have an extremely long life of service. Since the wear plates have no parts which project into the pulverizing zones,

these plates also will last for a long time before they will require replacement.

Having thus described my invention, what I claim as new and desire to secure by Letters Patent is:

l. Pulverizing apparatus comprising a generally circular disk rotatable about its axis, a series of impact elements of general L-shaped construction each having one leg forming a base in engagement with one side of the disk and another leg projecting from the front portion of the base and located in an approximately radial plane, a protective armor of extremely hard material secured to the front surface of each projecting leg, and a series of wear plates secured to the said side of the disk and clamping the base legs of the impact elements against the disk, the wear plates having openings therein through which the projecting legs of the impact elements extend.

2. Pulverizing apparatus comprising a generally circular disk rotatable about its axis, a series of impact elements of generally L-shaped construction each having one leg forming a base in engagement with one side of the disk, another leg projecting from the front portion of the base and located in an approximately radial plane, and ribs connecting the opposite edge portions of the projecting leg to the base leg, a protect-ive armor of extremely hard material secured to the front surface of each projecting leg, and a series of wear plates secured to the said side of the disk and clamping the base legs of the impact elements against the disk, the wear plates having approximately U-shaped openings therein through which the projecting legs and ribs of the impact elements extend.

3. Pulverizing apparatus comprising a general- .ly circular disk rotatable about its axis, a series of impact elements of generally L-shaped construction each having one leg forming a base in engagement with one side of the disk and another leg projecting from the front portion of the base and located in an approximately radial plane,

a protective armor of extremely hard material leg. a .b -.-l e.-.having a. hole. therethrough, a series of wear plates overlying the base legs and provided with holes which register with-the holes in-the base-lega t-he Wear-plates having openings therein-through Y which the projecting legs of" the impact elements extend, and-fasteningmeans extending through the holes-inthe wear plates and-base-legs -to-secure the-wear plates-'to the -diskandto -clampthe baselegs againstthe disk.

4. Pulverizing apparatus as set forth in claim 3, in which the disk is provided with holes which register with the holes in the base legs and wear plates, the fastening means being in the form of bolts extending through the registering holes.

5. Pulverizing apparatus as set forth in claim 3, in which the disk is provided with recesses within which the base legs of the impact elements are mounted.

6. Pulverizing apparatus as set forth in claim 3, in which the disk is provided with circular recesses, and the base legs are of circular shape and located within the said recesses.

7. As an article of manufacture, an impact element for a pulverizing apparatus comprising a generally L-shaped structure having one leg of generally circular cylindrical shape forming a base and another leg projecting from the front portion of the base parallel to the axis thereof, the base having a hole therethrough which is non-concentric therewith, ribs connecting the opposite edge portions of the projecting leg to the base leg, and a protective armor of extremely hard material secured to the front surface of the projecting leg.

8. As an article of manufacture, a wear plate for use with a hammer for the rotor disk of a pulverizing apparatus, the said plate being shaped substantially as a circular ring sector and having a hole therethrough for a fastener and an additional aperture therethrough for a projecting leg of hammer, the opening being located di rectly in front of the said hole and being of noncircular shape to lock the hammer against rotation.

9. As an article of manufacture, a wear plate for the rotor disk of a pulverizing apparatus, the said plate being shaped substantially as a circular ring sector and having a hole therethrough for a fastening means and an opening therethrough directly in front of the hole, the opening being shaped approximately as a U to receive the projecting leg and ribs of an impact element, the said U-shaped opening being situated in a position straddling said hole.

10. In a pulverizing apparatus having a generally circular disk rotatable about its axis, an impact element of generally L-shaped construction, a wear-plate, said impact element having one leg forming a base in engagement with one side of the disk and another leg projecting from the front portion of the base, said projecting leg having a flat face located in an approximately radial plane and having a protective armor of extremely hard material secured to said flat face, and a fastening means to clamp the base leg of the impact element between the wear-plate and the disk, the said wear-plate having an opening which is similar in cross-sectional shape to the projecting leg of the impact element and through which the said leg extends.

WAYNE C. ROGERS.

(References on following page) References Cited in the file of this patent UNITED STATES PATENTS Name Date Lipsey fl Jan. 16, 1877 Moore Jan. 8, 1878 Spensler Feb. 13, 1917 Kutasz ewicz May 25, 1926 Bell Sept. 7, 1926 7 Craig May 21, 1929 Riley et a1. May 20, 1930 8 Number Name Date; 4,941,923 Armour Jan.'2,-1934 1 2,566,103

Weston Y Aug: 28, 1951 OTHER REFERENCES,

Hard Surfacing by Fusion Welding, by Hqward S. Avery, Chapter '7 and "Chapter 17 (pages 41 to 44 and 94, New York Library Designation TA407A8 Copy 2). Copy in 241/300. 4 1 

